Improvement in head-blocks for saw-mills



UNITED STATES PATENT OEEIcE.

J. A. GBIGGS, OF CHARLESTON, ILLINOIS.

IMPROVEMENT IN HEAD-BLOCKS FOLR SAW-MILlLS.

Specification forming part of Letters Patent No. 56,929, dated August 7, 1866. Y i

To all whom it ma/y concern:

Be it rknown that I, J. A. GRIGGS, of Charleston, in the county of Coles and State of Illinois, have invented a new and usefulImprovement in Log-Setting Devices for Sawto the accompanying` drawings, forming part of this specitication, in whichr Figure l is a vertical section of my invention, taken in the line wat, Fig. 2; Fig. 2, a plan or top View of the same; Fig. 3, a detached inverted plan of one of the head-blocks pertaining to the same. Y

Similar letters of reference indicate like parts.

The object of this invention `is to obtain a device whereby logs may be set to a circular saw by the sawyer himself without the aid of an assistant; and it consists in setting the log by means of a bar or handle passing over the logl and saw and within convenient reach of the sawyer,`in connection with certain mechanism hereinafter described.

A A representthe carriage of a saw-mill; B B, the head-blocks, placed transversely thereon, and fitted between suitable guide- V blocks C C.

Dis a circular saw, the mandrel or arbor E of which is placed on a suitable framing, F. The parts above described may be constructed in the usual manner, and therefore do not require a special or minute description.

Gr is a rock-shaft, the ends of which pass into the guide-blocks C C, said blocks serving as bearings for the rock-shaft. 0n each end of this rock-shaft there is secured a metal plate, H, having two holes, aa, made in them to receive the inner ends ot' pawls I I', which rest upon springs J J, the latter having a tendency to keep the outer or free ends of the pawls engaged with racks K at the under sides of the head-blocks B B. The holes a a/ in each plate H are made at opposite sides of the axis of the rock-shaft G, so that when the latter is operated one pawl will engage with the rack K of its head-blockwhile the other is drawnpback. This will be fully understood by referring to Fig. 1.

L is a standard, rmly attached to the carriage, and LX is a toggle, which connects the upper end of the setting-lever M with the upper end of the standard L. rlo the lower arm ot' the toggle there is connected a bar or handle, N, which is retained in al1orizontal position, or about in that position, by a cord or chain, O, attached to a spring, P, secured to the upper end of the standard. The bar or handle N extends transversely over the carriage A A and within convenient reach of the Sawyer, who, when the mill is in operation, stands at the point *n From the above description it will be seen that the sawyer, by operating the bar or handle N, will actuate the toggle LX, setting-lever M, rock-shaft G, and the pawls I I, the

latter moving the head-blocks B B and setting the log to the saw.

By this arrangement the Sawyer is saved considerable labor, as the log may be set to the saw from a point or position where themechanism for gigging back the carriage may be set in motion. Considerable time is also saved thereby.

The invention is now in use, and about live hundred feet more of lumber, with one less hand, can be sawed in a day than. can be turned out by mills provided with the ordi- 4nary log-setting mechanism.

J. A. GRIGGS.

Witnesses:

S. H. NEsBrr, D. C. AMBLEE. 

